1. Field of the Invention
The present invention relates to an electric connecting apparatus for electrically connecting two electric components together by fitting an array of male terminals into an array of female terminals.
2. Description of the Related Art
This type of electric connecting apparatus is widely used for connection of, for example, electric components by means of an electric connection box of an automobile, connection of connectors of wiring harnesses. More specifically, an electric connection box of an automobile comprises an upper case and a lower case which are assembled together with electric components, such as bus bars and a wiring plate, intervened between both cases. Attached to the upper case are various kinds of electric components, such as a relay, fuse, connector, capacitor, diode, ECU (Electronic Control Unit) board, and PTC (Positive Temperature Coefficient). Of such electric components, for example, bus bar tabs and board terminals or bus bar tabs and connector terminals are in a male-female relationship. This permits those electric components to easily have an electric connection by a relative fitting action alone.
One specific example is disclosed in, for example, Japanese Unexamined Patent Publication (KOKAI) No. Hei 9-238419/1997. The main body of this prior art electric connection box has a bus-bar wiring plate from which a plurality of male terminals extend. An electronic board which is to be attached to the main body of the electric connection box is provided with female terminals at positions corresponding to the positions of the mating male terminals. As the electronic board is pressed into the main body, the female terminals are fitted over the mating male terminals.
This conventional electric connection box however requires that all the male terminals should be fitted into the respective female terminals at the same time when the electronic board is pressed into the main body of the electric connection box. In this case, the larger the number of terminals to be fitted together becomes, the greater the total inserting force required becomes according to the total number of the terminals, slight though the inserting force needed for each pair of a male terminal and a female terminal is.
Under such a situation, it demands a worker of a significant labor to manually attach an electronic board to the main body of an electric connection box. If the worker attempts to press the electronic board into the main body forcibly, some of the terminals may be damaged or broken. In this respect, special equipment for pressing an electronic board into the main body of an electric connection box in the step of attaching the electronic board in manufacturing the electric connection box. The use of such special equipment leads to an increased manufacturing cost of the electric connection box and is not suitable for mass production of electric connection boxes.
Accordingly, it is an object of the present invention to provide an electric connecting apparatus which can significantly reduce the required inserting force even when multiple male terminals and female terminals are needed to connect electric components together.
To achieve the above object, according to this invention, there is provided an electric connecting apparatus for electrically connecting two electric components together, which comprises an array of male terminals provided on one of the electric components; an array of female terminals provided on the other electric component; and time-lag application means for applying a time lag to initial contacts between the male terminals and the female terminals when the two electric components are connected together. The male terminals can respectively be fitted into the female terminals when the two electric components are connected together.
According to the electric connecting apparatus of this invention, the timing at which the inserting force that is needed for each of the array of male terminals reaches a peak in the process of connecting two electric components is not the same for the inserting force for the other male terminals, so that the required inserting forces for all the male terminals do not reach peaks at one time. This phenomenon is based on the following characteristic of a change in inserting force with respect to the amount of fitting of each male terminal into its mating female terminal after an initial contact therebetween. In general, at the time one male terminal is fitted into its mating female terminal, the required inserting force gradually increases from the point of the initial contact, reaches a peak when the amount of fitting of the male terminal increases to a certain level, and decreases thereafter as the male terminal is fitted deeper into the female terminal. It is often considered that the required inserting force of a male terminal into its mating female terminal reaches a peak when the portion of the female terminal where the male terminal contacts is widened most. Even when connecting two electric components requires a work of fitting multiple male terminals into the mating female terminals, therefore, an excessive labor is not needed for that fitting work, thus significantly reducing a burden on a worker.
When the time-lag application means includes a plurality of male terminals whose distal ends are at different positions from one another as seen in a fitting direction to the female terminals, those male terminals have initial contacts in an order from one whose distal end position is closer to the mating female terminal to one whose distal end position is farther to the mating female terminal at the time the two electric components are connected together. In this case, the plurality of male terminals may all have different lengths from one another, or may be classified into a type having relatively long lengths and a type having relatively short lengths. In either case, it is preferable that the time-lag application means should further include a plurality of female terminals having contacts to the male terminals at same positions as seen in the fitting direction of the male terminals.
The time-lag application means may include a spacer which gives an offset to proximal ends of the female terminals in the fitting direction of the male terminals. In this case, the amount of offset varies in accordance with the thickness of the spacer and the female terminals have initial contacts in an order from one which has a smaller amount of offset to one which has a larger amount of offset at the time the two electric components are connected together. It is preferable that the time-lag application means should further include a plurality of male terminals whose distal ends are all at the same position as seen in the fitting direction of the male terminals to the female terminals and that those male terminals should all have the same length.
Alternatively, the time-lag application means may include a plurality of female terminals having contacts to the male terminals at different positions from one another as seen in the fitting direction of the male terminals. In this case, those female terminals have initial contacts in an order from one whose contact position is closer to the distal end of the mating male terminal as seen in the fitting direction of the male terminal to one whose contact position is farther to the distal end of the mating male terminal at the time the two electric components are connected together. In this case, it is preferable that the time-lag application means should further include a plurality of male terminals whose distal ends are all at the same position as seen in the fitting direction of the male terminals to the female terminals and that the plurality of male terminals should all have the same length.
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific example, while indicating preferred embodiment of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.